From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 29463 invoked by alias); 17 Nov 2004 13:53:24 -0000 Mailing-List: contact gcc-help-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-help-owner@gcc.gnu.org Received: (qmail 29089 invoked from network); 17 Nov 2004 13:53:12 -0000 Received: from unknown (HELO nile.gnat.com) (205.232.38.5) by sourceware.org with SMTP; 17 Nov 2004 13:53:12 -0000 Received: from localhost (localhost [127.0.0.1]) by filtered-nile.gnat.com (Postfix) with ESMTP id BEF279691; Wed, 17 Nov 2004 08:53:11 -0500 (EST) Received: from nile.gnat.com ([127.0.0.1]) by localhost (nile.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 11265-01-8; Wed, 17 Nov 2004 08:53:11 -0500 (EST) Received: from [127.0.0.1] (taconic.gnat.com [205.232.38.103]) by nile.gnat.com (Postfix) with ESMTP id 6D2AF9690; Wed, 17 Nov 2004 08:53:11 -0500 (EST) Message-ID: <419B57C9.7060707@gnat.com> Date: Wed, 17 Nov 2004 13:53:00 -0000 From: Robert Dewar User-Agent: Mozilla Thunderbird 0.8 (Windows/20040913) MIME-Version: 1.0 To: Michael Matz Cc: Dave Korn , 'Gerald Pfeifer' , 'Beschorner Daniel' , gcc@gcc.gnu.org, gcc-help@gcc.gnu.org Subject: Re: gcc 3.3 / i386 / -O2 question References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new at nile.gnat.com X-SW-Source: 2004-11/txt/msg00112.txt.bz2 Michael Matz wrote: > While it's true that with signed arithmetic we are allowed to simply > break, such behaviour can (and in this case indeed does) point out a real > problem in the optimizers, so its often a bit too hasty to ignore a > problem just because the source code is not totally conformant. Interesting, though to be fair, David a couple of times said that it would be a good idea to try this code again with unsigned :-)